How to make a plastic barrel watertight?

[bario1]

Hi,

I have some 50l plastic barrels that I'm using as water butts. They had small drainage holes in the bottom originally, so i tried to block these up by cutting small bits of cork and jamming them in, then sealing them with B&Q exterior silicone sealant (the brown stuff). This worked fine for about 6 months, but i have noticed recently that the barrels are leaking, and when i checked, the sealant has perished and comes away from the surface of the barrel easily.

So - can anyone recommend a permanent way of blocking these little holes up?

[RaptorUK]

So - can anyone recommend a permanent way of blocking these little holes up?

If they are HDPE ( High-density polyethylene - Wikipedia, the free encyclopedia ) then you best option is to weld a patch over the top . . . it may sound like an involved job but with HDPE it's easily the most permanent method.

[Bill HH]

If they are HDPE ( High-density polyethylene - Wikipedia, the free encyclopedia ) then you best option is to weld a patch over the top . . . it may sound like an involved job but with HDPE it's easily the most permanent method.

When you say weld I presume you mean with chemical glue which melts the plastic as used for plumbing. Arc welding might be a little difficult. My advice is buy a new Butt and grow spuds in the old one.

[bario1]

Don't be silly Bill, you know how tight I am!

Raptor, can you give more info on how to 'weld' with plastic?

Thanks.

[RaptorUK]

When you say weld I presume you mean with chemical glue which melts the plastic as used for plumbing. Arc welding might be a little difficult.

Nope I mean with heat, just as with metal welding, melt the material to be welded and introduce a filler of the same material.

[RaptorUK]

Don't be silly Bill, you know how tight I am!

Raptor, can you give more info on how to 'weld' with plastic?

Thanks.

There are tools made for the job that use hot air at a controlled temperature, the pieces to be joined are heated and a filler also melted to strengthen the join.

I have a HDPE welding job to do on my IBC tank and will be attempting it using a gas soldering iron . . . once I figure out how to set and maintain the correct temperature. I bought some filler rods on ebay for a few £s and will be practicing on these.

[roitelet]

I have mended plastic water butts with a hot glue gun and it lasts fairly well. You need one that does not melt at a low temperature.

[Bill HH]

Put the butt onto a stand and a plant underneath and you will have automatic watering too! that should satisfy Mr, Tightwad lol.

You could always line it with plastic as long as you don't need a tap.

I think by the time you have bought all the stuff to plastic weld it you could have picked up another butt for a fiver. Oh and leaning into a butt whilst melting plastic is well dangerous, get a friend to do it.

[Bill HH]

I wonder if spraying the bottom with expanded foam would work? it takes weeks to get it off my hands.

[veggiechicken]

Can you coat the inside of the barrel with summat to cover the holes?
I've no idea what as I'm not DIYer but I'm sure there must be some sort of sealant!

[bario1]

Maybe this stuff?

http://www.innotecworld.com/products...p?productid=29

[Jeanied]

I bought some of this stuff a few years ago -and have fixed plastic watering cans, guttering and waterbutts with it. I reckon it has paid for itself by now

[bario1]

I think by the time you have bought all the stuff to plastic weld it you could have picked up another butt for a fiver.

Where do you get your £5 water butts from?? Anyway, I have four of these to fix!

[RaptorUK]

Maybe this stuff?

http://www.innotecworld.com/products...p?productid=29

You would probably need to use the primer with that if your butt is HDPE http://www.innotecworld.com/products...?productid=199

[bario1]

Bloody Hell, £20 a tin!